Proof press



June 26, 1934- R. o. vANDERcooK Er AL 1,964,488

PROOF PRESS Filed Deo. 22. 1933 2 Sheets-Sheet 1- June 26, 1934. R. o. vANDERcooK ET AL PROOF PRES S Filed Dec. 22. 1935 2 Sheets-Sheet 2 Y. fz.. .Idilllclww 00,4( M n eraan/. der na.

Patented June 26, 1.934

UNITED STATES PATENT OFFICE PROOF PRESS Application December 22, 1933,v Serial No. 703,518

Claims'.

|This invention relates to printing' presses, par-v ticularly proof presses and involves improved structure and operation for assuring at all times clean and clear-cut printing,

5 In the printing of proofs, the ordinary practice is to lay the proof sheet fiat on the inked form, then pass the printing roller thereover,

and then remove the printed proof sheet from' the form. With such procedure, requiring the direct Amanual application of the sheet to the inked form and removal thereof after printing, the least lateral displacement of the sheet while on the form Will cause smudging, and the length of time of contact of the entire sheet with the inked form may permit the sheet to take on ink unevenly, and the result is that the proof printing is not as clean and clear-cut as it should be. The important object of our invention is to provide supporting and guide means associated with the printing roller and in which a sheet is inserted downwardly in front of the roller and with its ends properly aligned below the pressure or printing line of the roller so that when the roller travels across the inked form, the sheet will be applied to the inked surface only along the printing or pressure line of the roller as the roller progressively applies the sheet to the form, but with the ends of the sheet at opposite sides of the printing line held by the guide means away from the form, so that there is only momentary progressive printing engagenient of the sheet with the form as the sheet is progressively applied thereto by the roller.

From the accompanying drawings, which incorporate the above referred to and other fea-J tures of our invention, and from the following specification, the advantages of our invention will be apparent.

On the drawings:

Figure 1 is a front elevation of a proof press, partially in section on plane I-I Figure 2; and

Figure 2 is a left end elevation.

The press shown comprises the top frame or bed 10 presenting the horizontal top surface 11 on which printing forms F are supported.` This top frame is supported at its corners by suitable legs 12, shown as angle bars. At its front and rear side the vframe has the vertical extensions or walls 13 with rail flanges 14 thereon.

The carriage for supporting the printing roller 15 comprises end walls or plates 16 and 16 rigidly connected and spaced at their upper ends by a cross bar 17 extending vertically above and parallel with the printing roller axis, and at their (Cl. lill-272) lower ends are rigidly secured and spaced by a. cross bar 18 extending below the bed plate 10.

'Ihe core 15 of the printing roll is detachably coupled by pins 19 with metal rollers 20 and 20 concentric therewith, these rollers having track age on top of the rail flanges 14. The stub shafts 21 on the rollers 20 are journalled by suitable anti-friction bearings 22 in the carriage end walls 16 and 16 respectively. The under-i side of each rail flange is engaged by a pair of rollers 23 and 24 journalled by adjustable stub shafts 25 secured in the respective end wall of the carriage, the rollers 23 and 24 being at opposite sides of the axis of the printing roll so that the carriage is accurately supported in vertical position on the rail ilanges. Secured to the outer ends of the upper cross bar 17 are suitable knobs 26 by means of which the carriage may be readily moved back and forth across the printing bed, such movement of the carriage causing rotation of the printing roll.

At the ends of the rail flanges are abutment blocks 27 which limit the carriage travel.

Describing now the means for carrying out our improved procedure of proof printing, such means 30 is shown in the form of fittings or attachments designated as a whole G and supported on the carriage upper cross bar 17. Each fitting comprises an upper wall or plate 28 having a lug 29 on the top thereof which may be formed integral therewith or detachably secured as by means of screws 30, this lug being placed midway between the ends of the plate and recessed to form with the plate a polygonal opening 3l, the opening shown being of square cross-section to receive the cross bar 17 of similar cross-section. Depending from this top plate 28 is a trough shaped frame 32 whose legs 33 are slanted or inclined outwardly from the vertical axis of the frame, the ends of which legs abut the inner side of the upper wall 28 and are secured thereto as by means of screws 34. Two of these fittings G are provided and their cross frames receive and surround the printing roll 15, the inner bottom surface of the frame being substantially semi-circular and concentric with the printing roll axis but with a radius slightly greater than that of the printing roll to leave clearance space 35 for passage of the sheets to be printed, the depth of the clearance space being slightly greater than the thickness of the sheets.

A sheet S to be printed is slipped down along the inner faces of the frame legs 33 in front of the printingk roll into position ready for application of the sheet by the roll to the form on the r printing bed. By means of set screws 36 the fittings G are held in adjusted position on the cross bar 17 with the distance between the inner faces of the fitting upper walls 28 equal substantially to the width of the sheets to be printed, these inner faces serving to laterally align the sheet relative to the printing roll and the form on the printing bed.

The fittings G are symmetrical at opposite sides of the vertical axial plane passing through the printing roll axis so that sheets can be inserted at either side thereof for corresponding direction of travel of the carriage across the printing form. In the bottom wall of each of the fitting frames 33 slots 37 and 37', or other guide means, may be provided for assisting in the proper alignment of a sheet partway around the printing roll ready for a printing operation. The frames 33 may also be provided with bumper nipples or projections 38-38 which engage with the body of the form, should the form .become displaced, so as to protect the type or printing surface of the form from abrasion or injury.

Describing now the operation, Figure 1, full lines, shows the carriage at the left end of the bed plate, the form F to be printed being supported on the bed in proper alignment relative to the iittings G so that the depending frames 33 will pass along at opposite sides of the form when the carriagey is moved toward the right. The sheet S is inserted into the iittings G to be aligned between the inner faces of the top plates 28 and to rest against the inner faces of the legs 33 in front of the printing roll, and with the sheet drawn around the roll a distance up to the gage marks or stops 37. The outer end of the sheet will extend a distance beyond the upper ends of the legs 33 which ends are rounded so that the sheet may gradually droop outwardly.

As the carriage is now shifted toward the right, the end of the sheet below the printing roll will be applied to the inked form and the sheet will be progressively applied to the form as the roll rolls over the form and the sheet travels up the trailing legs 33 of the iittings G ready to be withdrawn when the roller has traveled across the form and the printing has been completed on the sheet. The sheet does not touch the inked surface of the form until it is carried and applied thereto by the printing roll and then, during the entire travel of the roll across the printing fo-rm, the sheet engages the printing forni only along the line of tangential contact of the form with the sheet around the roll, the ends of the sheet at either side of this contact or printing line being held away from the inked surface by the guide lugs 33 of the guide iittings G. The printing contact of the sheet with the printing form is therefore progressive and momentary. The sheet is accurately aligned longitudinally and transversely by the guide fittings and will be progressively applied to the fitting form without any lateral displacement of the sheet, and as the momentary printing contact does not permit the accumulation of surplus ink on the sheet, the printing will be precise, clear-cut, and clean. The guide frames 32 at no time contact with the printed matter on the sheet and when the carriage reaches the end of its printing stroke, the printed sheet will be shifted out for ready removal from the guide structure.

When the carriage reaches the end of its stroke in one direction, another sheet can be fed into the guide structure for printing of the sheet during opposite direction of travel of the carriage.

In other words, the guide structure functions for either direction of travel of the carriage across the printing form. The dotted lines in Figure l show the carriage in midway position on the printing bed.

Should the printing form be out of alignment with the guide structures, or become displaced when the carriage approaches, the abutment 38 or 38 will strike the body of the printing form and so prevent the guide structures from striking and marring the form printing surface.

With our simple and economically manufactured supporting and guide structure applied to a proof press, it is possible to easily and accurately print proofs of a quality heretofore unobtainable.

We have shown a practical and efficient embodiment of our invention but we do not desire to be limited to the exact construction, arrangement and operation shown and described as changes and modifications may be made without departing from the scope of the invention as deiined in the appended claims.

We claim as follows:

1. In a printing press, a form supporting bed plate, a roll carriage, supporting and guide rails for the carriage, a printing roll journalled on the carriage, spaced apart guide structures on said carriage comprising trough shaped frames receiving the printing roll and with their legs extending upwardly at opposite sides of the roll, said guide structures serving to receive and align a sheet with its lower end extended partway around the printing roll and for progressive application of the sheet to the printing form along the printing or pressure line of the roll and for holding the ends of the sheet at opposite sides of the printing line away from the printing form as the sheet travels and is guided through the guide structure during such printing operation.

2. In a proof press, a printing form supporting 115 bed plate, a carriage, a printing roll journalled on the carriage to be carried across the printing form thereby, a pair of trough shaped guide frames supported on said carriage to straddle the printing roll with their legs extending up- 120 wardly at opposite sides of the roll, said frames being spaced apart to receive a sheet to be printed at its longitudinal margins and serving to guide the sheet in contact with the printing line of the roll as the sheet is progressively applied 125 by the roll to the printing form for printing thereof, said frames holding the sheet at opposite sides of the printing line away from the printing form during such printing operation.

3. In a proof press, a printing form supporting bed, a carriage movable back and forth on said bed, a printing roll journalled on said carriage for printing cooperation with the form, and a pair of guide troughs supported by the carriage and extending around the bottom of the roll, said guide troughs receiving a sheet to be printed and guiding the sheet from one side of the roll to the other and with its ends elevated so that, when the sheet is progressively applied to the printing form by the roll, the sheet will engage with the form only along such printing line.

4. In a proof press, a printing form supporting bed, a carriage movable back and forth on said bed, a printing roll journalled on said carriage for passage over the printing form with the carriage, a pair of guide frames on the carriage in the form of troughs receiving the roll with their bottoms paralleling the roll and with their sides extending tangentially at opposite sides of the roll 150 and inclined away therefrom, said frames being spaced apart to receive the sheet to be printed along its longitudinal margin and to align the sheet with its lower end extending partway around the roll, whereby as said carriage travels said roll will progressively apply the sheet to the printing form with the sheet at opposite sides of the printing line being held by the guide frames away from the printing form.

5. In a proof press comprising a printing form supporting bed, a carriage adapted for back and forth travel on said bed, and a printing roll mounted-on said carriage, a pair of guide structures on the carriage receiving the printing roll, the bottoms of said frames circumferentially paralleling the roll and the sides of the frames extending upwardly and inclined outwardly from the vertical, said frames being adjustable and spaced apart for engagement of their sides with the longitudinal margins of a sheet to be printed, means on said frames for aligning a sheet received thereby with its lower end extended partway around the bottom of the printing roll, whereby, when said carriage is shifted past the printing form on the bed, the printing roll will progressively apply the sheet to the printing form for progressive printing thereof but said frames will guide the sheet and hold it away from the printing form except where the sheet is engaged by the roll with the form during progressive printing thereof.

ROBERT O. VANDERCOOK. EDWARD O. VANDERCOOK. DAVID D. VANDERCOOK. FREDERICK R. VANDERCOOK. 

